1. Field of the Invention
The present invention relates to cushions or other devices that can be selectively cooled (or heated) by the user and an improved thermoelectric heat pump for use in such applications.
2. Description of the Related Art
Air-conditioned seats are a reality in many luxury-car brands being sold in the United States. The configuration and advantages of such seats were described in two of Steve Feher's recent patents, U.S. Pat. Nos. 6,263,530 and 6,085,369. These seats work satisfactorily such that they have become a popular option for Lexus, Lincoln and other automakers, but efforts are ongoing to improve the operating efficiency and compactness of the associated heat pumps to cool better, use less energy and occupy less space.
Besides merely reducing the temperature of the air within the seats and that bleeds through the seat covers, it would also be desirable to reduce the relative humidity of that air to enhance the user's comfort. To do so it is necessary to further cool the air below the dew point, dispose of the resulting condensation, and then reheat the air to a more comfortable temperature (but lower relative humidity) for distribution inside the seat. Preferably, the condensation is disposed of by evaporating it into the larger volume of air outside the seat. At the same time, it is desirable to reduce the electrical power requirements for the heat pump and decrease the volume of space required for the pump. These objectives are addressed by the subject disclosure which significantly improves the cooling element of today's air-conditioned seats.
As mentioned above, the technology of the present invention has other applications in addition to vehicle cushions, for example, bedding such as mattress pads and mattresses as mentioned in Steve Feher's '530 and '369 patents and as disclosed in his earlier U.S. Pat. No. 4,777,802. Additionally, Feher has been developing this technology specifically for use in pillows and pillow cases. Physiologically, the head is among the best places in the human body to remove heat from (or add heat to) because of the large amount of circulation in the head and scalp. Accordingly, effective cooling (or warming) of the human body can be achieved to a large extent by cooling (or warming) the head, providing improved user comfort in all types of weather, but especially hot, humid weather.
Conditioning the air inside a pillow or pillow case presents certain challenges, however. The pillow must be as quiet as possible since the user's ear may be in direct contact with the pillow. Further, attention should be paid to the sleeping surface of the pillow that it is kept as comfortable and aesthetically appealing as possible. These objectives are addressed as well in the disclosure that follows.